where do I get a client

I am new to Facebook based development and just require a basic Facebook registration form, I've found the "registration form and its html to embed into my website", but need a client_id so I can use it. Where do I get this from?

What is a client_id?

The client_id is a public identifier for apps. Even though it's public, it's best that it isn't guessable by third parties, so many implementations use something like a 32-character hex string. If the client ID is guessable, it makes it slightly easier to craft phishing attacks against arbitrary applications.

Where can I get my client ID?

Your client ID , also referred to as a UCI , is on all documents you get from us. It is an eight or ten-digit number that looks like this: 0000-0000 or 00-0000-0000. If you are applying to us for the first time, you will not yet have a client ID .

http://developers.facebook.com/apps

After creating an app, the App ID / Client ID is shown.